public static void rewriteFakeMethod(CodeIterator methodBody, String methodDescriptor) {
String ret = DescriptorUtils.getReturnType(methodDescriptor);
// if the return type is larger than one then it is not a primitive
// so it does not need to be boxed
if (ret.length() != 1) {
return;
}
byte ar = (byte) Opcode.ARETURN;
byte[] areturn = {ar};
// void methods are special
if (ret.equals("V")) {
while (methodBody.hasNext()) {
try {
int index = methodBody.next();
int opcode = methodBody.byteAt(index);
// replace a RETURN opcode with
// ACONST_NULL
// ARETURN
// to return a null value
if (opcode == Opcode.RETURN) {
Bytecode code = new Bytecode(methodBody.get().getConstPool());
code.add(Opcode.ACONST_NULL);
code.add(Opcode.ARETURN);
methodBody.insertAt(index, code.get());
}
} catch (BadBytecode e) {
throw new RuntimeException(e);
}
}
} else {
while (methodBody.hasNext()) {
try {
int index = methodBody.next();
int opcode = methodBody.byteAt(index);
switch (opcode) {
case Opcode.IRETURN:
case Opcode.LRETURN:
case Opcode.DRETURN:
case Opcode.FRETURN:
// write a NOP over the old return instruction
// insert the boxing code to get an object on the stack
Bytecode b = new Bytecode(methodBody.get().getConstPool());
Boxing.box(b, ret.charAt(0));
b.addOpcode(Opcode.ARETURN);
methodBody.insertAt(index, b.get());
}
} catch (BadBytecode e) {
throw new RuntimeException(e);
}
}
}
}
@Override
protected void onApply(CtBehavior behavior, Bytecode bytecode) throws BadBytecode {
bytecode = BytecodeTools.prepareMethodForBytecode(behavior, bytecode);
// loop through the opcodes and change any GT/GE opcodes to ICMPGT/ICMPGE
CodeIterator iterator = behavior.getMethodInfo().getCodeAttribute().iterator();
while (iterator.hasNext()) {
int index = iterator.next();
int opcode = iterator.byteAt(index);
switch (opcode) {
case Opcode.IFGT:
// overwrite the opcode
iterator.writeByte(Opcode.IF_ICMPGT, index);
// insert the method call
iterator.insertAt(index, bytecode.get());
behavior.getMethodInfo().getCodeAttribute().computeMaxStack();
break;
case Opcode.IFGE:
// overwrite the opcode
iterator.writeByte(Opcode.IF_ICMPGE, index);
// insert the method call
iterator.insertAt(index, bytecode.get());
behavior.getMethodInfo().getCodeAttribute().computeMaxStack();
break;
}
}
}
private void initExtraHarvest() {
try {
CtClass terraForming =
HookManager.getInstance()
.getClassPool()
.get("com.wurmonline.server.behaviours.Terraforming");
CtClass[] paramTypes = {
HookManager.getInstance().getClassPool().get("com.wurmonline.server.creatures.Creature"),
CtPrimitiveType.intType,
CtPrimitiveType.intType,
CtPrimitiveType.booleanType,
CtPrimitiveType.intType,
CtPrimitiveType.floatType,
HookManager.getInstance().getClassPool().get("com.wurmonline.server.items.Item")
};
CtMethod method =
terraForming.getMethod(
"harvest", Descriptor.ofMethod(CtPrimitiveType.booleanType, paramTypes));
MethodInfo methodInfo = method.getMethodInfo();
CodeAttribute codeAttribute = methodInfo.getCodeAttribute();
CodeIterator codeIterator = codeAttribute.iterator();
LocalVariableAttribute attr =
(LocalVariableAttribute) codeAttribute.getAttribute(LocalVariableAttribute.tag);
int quantityIndex = -1;
for (int i = 0; i < attr.tableLength(); i++) {
if ("quantity".equals(attr.variableName(i))) {
quantityIndex = attr.index(i);
}
}
if (quantityIndex == -1) {
throw new HookException("Quantity variable can not be resolved");
}
while (codeIterator.hasNext()) {
int pos = codeIterator.next();
int op = codeIterator.byteAt(pos);
if (op == CodeIterator.ISTORE) {
int fieldRefIdx = codeIterator.byteAt(pos + 1);
if (quantityIndex == fieldRefIdx) {
Bytecode bytecode = new Bytecode(codeIterator.get().getConstPool());
bytecode.addIconst(extraHarvest);
bytecode.add(Bytecode.IADD);
codeIterator.insertAt(pos, bytecode.get());
break;
}
}
}
} catch (NotFoundException | BadBytecode e) {
throw new HookException(e);
}
}
protected void enhanceAttributesAccess(
CtClass managedCtClass,
IdentityHashMap<String, PersistentAttributeAccessMethods> attributeDescriptorMap) {
final ConstPool constPool = managedCtClass.getClassFile().getConstPool();
for (Object oMethod : managedCtClass.getClassFile().getMethods()) {
final MethodInfo methodInfo = (MethodInfo) oMethod;
final String methodName = methodInfo.getName();
// skip methods added by enhancement and abstract methods (methods without any code)
if (methodName.startsWith("$$_hibernate_") || methodInfo.getCodeAttribute() == null) {
continue;
}
try {
final CodeIterator itr = methodInfo.getCodeAttribute().iterator();
while (itr.hasNext()) {
final int index = itr.next();
final int op = itr.byteAt(index);
if (op != Opcode.PUTFIELD && op != Opcode.GETFIELD) {
continue;
}
final String fieldName = constPool.getFieldrefName(itr.u16bitAt(index + 1));
final PersistentAttributeAccessMethods attributeMethods =
attributeDescriptorMap.get(fieldName);
// its not a field we have enhanced for interception, so skip it
if (attributeMethods == null) {
continue;
}
// System.out.printf( "Transforming access to field [%s] from method [%s]%n", fieldName,
// methodName );
log.debugf("Transforming access to field [%s] from method [%s]", fieldName, methodName);
if (op == Opcode.GETFIELD) {
final int methodIndex = MethodWriter.addMethod(constPool, attributeMethods.getReader());
itr.writeByte(Opcode.INVOKESPECIAL, index);
itr.write16bit(methodIndex, index + 1);
} else {
final int methodIndex = MethodWriter.addMethod(constPool, attributeMethods.getWriter());
itr.writeByte(Opcode.INVOKESPECIAL, index);
itr.write16bit(methodIndex, index + 1);
}
}
methodInfo.getCodeAttribute().setAttribute(MapMaker.make(classPool, methodInfo));
} catch (BadBytecode bb) {
final String msg =
String.format(
"Unable to perform field access transformation in method [%s]", methodName);
throw new EnhancementException(msg, bb);
}
}
}
protected void enhanceAttributesAccess(Map<String, CtField> fieldsMap, CtClass managedCtClass)
throws Exception {
final ConstPool constPool = managedCtClass.getClassFile().getConstPool();
final ClassPool classPool = managedCtClass.getClassPool();
for (Object oMethod : managedCtClass.getClassFile().getMethods()) {
final MethodInfo methodInfo = (MethodInfo) oMethod;
final String methodName = methodInfo.getName();
// skip methods added by enhancement, and abstract methods (methods without any code)
if (methodName.startsWith(DROOLS_PREFIX) || methodInfo.getCodeAttribute() == null) {
continue;
}
try {
final CodeIterator itr = methodInfo.getCodeAttribute().iterator();
while (itr.hasNext()) {
final int index = itr.next();
final int op = itr.byteAt(index);
if (op != Opcode.PUTFIELD && op != Opcode.GETFIELD) {
continue;
}
final String fieldName = constPool.getFieldrefName(itr.u16bitAt(index + 1));
CtField ctField = fieldsMap.get(fieldName);
if (ctField == null) {
continue;
}
// if we are in constructors, only need to intercept assignment statement for Reactive
// Collection/List/... (regardless they may be final)
if (methodInfo.isConstructor() && !(isCtFieldACollection(ctField))) {
continue;
}
if (op == Opcode.PUTFIELD) {
// addMethod is a safe add, if constant already present it return the existing value
// without adding.
final int methodIndex = addMethod(constPool, writeMethods.get(fieldName));
itr.writeByte(Opcode.INVOKEVIRTUAL, index);
itr.write16bit(methodIndex, index + 1);
}
}
methodInfo.getCodeAttribute().setAttribute(MapMaker.make(classPool, methodInfo));
} catch (BadBytecode bb) {
final String msg =
String.format(
"Unable to perform field access transformation in method [%s]", methodName);
throw new Exception(msg, bb);
}
}
}
/** Prints the bytecode instructions of a given method. */
public void print(CtMethod method) {
MethodInfo info = method.getMethodInfo2();
ConstPool pool = info.getConstPool();
CodeAttribute code = info.getCodeAttribute();
if (code == null) return;
CodeIterator iterator = code.iterator();
while (iterator.hasNext()) {
int pos;
try {
pos = iterator.next();
} catch (BadBytecode e) {
throw new RuntimeException(e);
}
stream.println(pos + ": " + instructionString(iterator, pos, pool));
}
}
/**
* @param lessThan If the index of the local variable is less than this value, it does not change.
* Otherwise, the index is increased.
* @param delta the indexes of the local variables are increased by this value.
*/
private static void shiftIndex(CodeIterator ci, int lessThan, int delta) throws BadBytecode {
int index = ci.next();
int opcode = ci.byteAt(index);
if (opcode < ILOAD) return;
else if (opcode < IASTORE) {
if (opcode < ILOAD_0) {
// iload, lload, fload, dload, aload
shiftIndex8(ci, index, opcode, lessThan, delta);
} else if (opcode < IALOAD) {
// iload_0, ..., aload_3
shiftIndex0(ci, index, opcode, lessThan, delta, ILOAD_0, ILOAD);
} else if (opcode < ISTORE) return;
else if (opcode < ISTORE_0) {
// istore, lstore, ...
shiftIndex8(ci, index, opcode, lessThan, delta);
} else {
// istore_0, ..., astore_3
shiftIndex0(ci, index, opcode, lessThan, delta, ISTORE_0, ISTORE);
}
} else if (opcode == IINC) {
int var = ci.byteAt(index + 1);
if (var < lessThan) return;
var += delta;
if (var < 0x100) ci.writeByte(var, index + 1);
else {
int plus = (byte) ci.byteAt(index + 2);
int pos = ci.insertExGap(3);
ci.writeByte(WIDE, pos - 3);
ci.writeByte(IINC, pos - 2);
ci.write16bit(var, pos - 1);
ci.write16bit(plus, pos + 1);
}
} else if (opcode == RET) shiftIndex8(ci, index, opcode, lessThan, delta);
else if (opcode == WIDE) {
int var = ci.u16bitAt(index + 2);
if (var < lessThan) return;
var += delta;
ci.write16bit(var, index + 2);
}
}
public boolean transformClass(ClassFile file, ClassLoader loader, boolean modifiableClass) {
Set<Integer> methodCallLocations = new HashSet<Integer>();
Integer newCallLocation = null;
Integer methodReflectionLocation = null;
Integer fakeCallRequiredLocation = null;
// first we need to scan the constant pool looking for
// CONSTANT_method_info_ref structures
ConstPool pool = file.getConstPool();
for (int i = 1; i < pool.getSize(); ++i) {
// we have a method call
if (pool.getTag(i) == ConstPool.CONST_Methodref) {
String className = pool.getMethodrefClassName(i);
String methodName = pool.getMethodrefName(i);
if (className.equals(Method.class.getName())) {
if (methodName.equals("invoke")) {
// store the location in the const pool of the method ref
methodCallLocations.add(i);
// we have found a method call
// if we have not already stored a reference to our new
// method in the const pool
if (newCallLocation == null) {
methodReflectionLocation =
pool.addClassInfo("org.fakereplace.reflection.MethodReflection");
int nt = pool.addNameAndTypeInfo("fakeCallRequired", "(Ljava/lang/reflect/Method;)Z");
fakeCallRequiredLocation = pool.addMethodrefInfo(methodReflectionLocation, nt);
newCallLocation = pool.addNameAndTypeInfo(METHOD_NAME, REPLACED_METHOD_DESCRIPTOR);
}
}
}
}
}
// this means we found an instance of the call, now we have to iterate
// through the methods and replace instances of the call
if (newCallLocation != null) {
List<MethodInfo> methods = file.getMethods();
for (MethodInfo m : methods) {
try {
// ignore abstract methods
if (m.getCodeAttribute() == null) {
continue;
}
CodeIterator it = m.getCodeAttribute().iterator();
while (it.hasNext()) {
// loop through the bytecode
int index = it.next();
int op = it.byteAt(index);
// if the bytecode is a method invocation
if (op == CodeIterator.INVOKEVIRTUAL) {
int val = it.s16bitAt(index + 1);
// if the method call is one of the methods we are
// replacing
if (methodCallLocations.contains(val)) {
Bytecode b = new Bytecode(file.getConstPool());
// our stack looks like Method, instance,params
// we need Method, instance, params , Method
b.add(Opcode.DUP_X2);
b.add(Opcode.POP);
b.add(Opcode.DUP_X2);
b.add(Opcode.POP);
b.add(Opcode.DUP_X2);
b.addInvokestatic(
methodReflectionLocation, "fakeCallRequired", "(Ljava/lang/reflect/Method;)Z");
b.add(Opcode.IFEQ);
JumpMarker performRealCall = JumpUtils.addJumpInstruction(b);
// now perform the fake call
b.addInvokestatic(methodReflectionLocation, "invoke", REPLACED_METHOD_DESCRIPTOR);
b.add(Opcode.GOTO);
JumpMarker finish = JumpUtils.addJumpInstruction(b);
performRealCall.mark();
b.addInvokevirtual(Method.class.getName(), METHOD_NAME, METHOD_DESCRIPTOR);
finish.mark();
it.writeByte(CodeIterator.NOP, index);
it.writeByte(CodeIterator.NOP, index + 1);
it.writeByte(CodeIterator.NOP, index + 2);
it.insert(b.get());
}
}
}
m.getCodeAttribute().computeMaxStack();
} catch (Exception e) {
log.error("Bad byte code transforming " + file.getName());
e.printStackTrace();
}
}
return true;
} else {
return false;
}
}
/**
* Replace access to fields of entities (for example, entity.field) with a call to the enhanced
* getter / setter (in this example, entity.$$_hibernate_read_field()). It's assumed that the
* target entity is enhanced as well.
*
* @param managedCtClass Class to enhance
*/
public void enhanceFieldAccess(CtClass managedCtClass) {
final ConstPool constPool = managedCtClass.getClassFile().getConstPool();
for (Object oMethod : managedCtClass.getClassFile().getMethods()) {
final MethodInfo methodInfo = (MethodInfo) oMethod;
final String methodName = methodInfo.getName();
// skip methods added by enhancement and abstract methods (methods without any code)
if (methodName.startsWith("$$_hibernate_") || methodInfo.getCodeAttribute() == null) {
continue;
}
try {
final CodeIterator itr = methodInfo.getCodeAttribute().iterator();
while (itr.hasNext()) {
int index = itr.next();
int op = itr.byteAt(index);
if (op != Opcode.PUTFIELD && op != Opcode.GETFIELD) {
continue;
}
String fieldName = constPool.getFieldrefName(itr.u16bitAt(index + 1));
String fieldClassName =
constPool.getClassInfo(constPool.getFieldrefClass(itr.u16bitAt(index + 1)));
CtClass targetCtClass = this.classPool.getCtClass(fieldClassName);
if (!enhancementContext.isEntityClass(targetCtClass)
&& !enhancementContext.isCompositeClass(targetCtClass)) {
continue;
}
if (targetCtClass == managedCtClass
|| !enhancementContext.isPersistentField(targetCtClass.getField(fieldName))
|| "this$0".equals(fieldName)) {
continue;
}
log.debugf("Transforming access to field [%s] from method [%s]", fieldName, methodName);
if (op == Opcode.GETFIELD) {
int fieldReaderMethodIndex =
constPool.addMethodrefInfo(
constPool.addClassInfo(fieldClassName),
EnhancerConstants.PERSISTENT_FIELD_READER_PREFIX + fieldName,
"()" + constPool.getFieldrefType(itr.u16bitAt(index + 1)));
itr.writeByte(Opcode.INVOKEVIRTUAL, index);
itr.write16bit(fieldReaderMethodIndex, index + 1);
} else {
int fieldWriterMethodIndex =
constPool.addMethodrefInfo(
constPool.addClassInfo(fieldClassName),
EnhancerConstants.PERSISTENT_FIELD_WRITER_PREFIX + fieldName,
"(" + constPool.getFieldrefType(itr.u16bitAt(index + 1)) + ")V");
itr.writeByte(Opcode.INVOKEVIRTUAL, index);
itr.write16bit(fieldWriterMethodIndex, index + 1);
}
}
methodInfo.getCodeAttribute().setAttribute(MapMaker.make(classPool, methodInfo));
} catch (BadBytecode bb) {
final String msg =
String.format(
"Unable to perform field access transformation in method [%s]", methodName);
throw new EnhancementException(msg, bb);
} catch (NotFoundException nfe) {
final String msg =
String.format(
"Unable to perform field access transformation in method [%s]", methodName);
throw new EnhancementException(msg, nfe);
}
}
}
public boolean match(String filename, ClassFile classFile, ClassMap tempClassMap) {
for (Object o : classFile.getMethods()) {
MethodInfo methodInfo = (MethodInfo) o;
classMod.methodInfo = methodInfo;
CodeAttribute codeAttribute = methodInfo.getCodeAttribute();
if (codeAttribute == null) {
continue;
}
if (getClassMap().hasMap(deobfMethod)) {
MethodRef obfTarget = (MethodRef) getClassMap().map(deobfMethod);
if (!methodInfo.getName().equals(obfTarget.getName())) {
continue;
}
}
ArrayList<String> deobfTypes = null;
ArrayList<String> obfTypes = null;
if (deobfMethod != null && deobfMethod.getType() != null) {
deobfTypes = ConstPoolUtils.parseDescriptor(deobfMethod.getType());
obfTypes = ConstPoolUtils.parseDescriptor(methodInfo.getDescriptor());
if (!isPotentialTypeMatch(deobfTypes, obfTypes)) {
continue;
}
}
ConstPool constPool = methodInfo.getConstPool();
CodeIterator codeIterator = codeAttribute.iterator();
initMatcher();
ArrayList<JavaRef> tempMappings = new ArrayList<JavaRef>();
try {
match:
for (int offset = 0;
offset < codeIterator.getCodeLength() && matcher.match(methodInfo, offset);
offset = codeIterator.next()) {
tempMappings.clear();
for (Map.Entry<Integer, JavaRef> entry : xrefs.entrySet()) {
int captureGroup = entry.getKey();
JavaRef xref = entry.getValue();
byte[] code = matcher.getCaptureGroup(captureGroup);
int index = Util.demarshal(code, 1, 2);
ConstPoolUtils.matchOpcodeToRefType(code[0], xref);
ConstPoolUtils.matchConstPoolTagToRefType(constPool.getTag(index), xref);
JavaRef newRef = ConstPoolUtils.getRefForIndex(constPool, index);
if (!isPotentialTypeMatch(xref.getType(), newRef.getType())) {
if (deobfMethod != null) {
Logger.log(
Logger.LOG_METHOD,
"method %s %s matches %s %s, but",
methodInfo.getName(),
methodInfo.getDescriptor(),
deobfMethod.getName(),
deobfMethod.getType());
}
Logger.log(
Logger.LOG_METHOD,
"method %s %s failed xref #%d %s %s -> %s %s",
methodInfo.getName(),
methodInfo.getDescriptor(),
captureGroup,
xref.getName(),
xref.getType(),
newRef.getName(),
newRef.getType());
continue match;
}
tempMappings.add(xref);
tempMappings.add(newRef);
}
for (int i = 0; i + 1 < tempMappings.size(); i += 2) {
tempClassMap.addMap(tempMappings.get(i), tempMappings.get(i + 1));
}
if (deobfMethod != null) {
String deobfName = classMod.getDeobfClass();
tempClassMap.addClassMap(deobfName, ClassMap.filenameToClassName(filename));
tempClassMap.addMethodMap(
deobfName, deobfMethod.getName(), methodInfo.getName(), methodInfo.getDescriptor());
if (deobfTypes != null && obfTypes != null) {
for (int i = 0; i < deobfTypes.size(); i++) {
String desc = ClassMap.descriptorToClassName(deobfTypes.get(i));
String obf = ClassMap.descriptorToClassName(obfTypes.get(i));
if (!obf.equals(desc)) {
tempClassMap.addClassMap(desc, obf);
}
}
}
}
afterMatch(classFile, methodInfo);
classMod.methodInfo = null;
return true;
}
} catch (BadBytecode e) {
Logger.log(e);
}
}
classMod.methodInfo = null;
return false;
}
protected void checkClassFile(ClassFile file) throws Exception {
Map<Integer, Triple> calls = new HashMap<>();
ConstPool pool = file.getConstPool();
for (int i = 1; i < pool.getSize(); ++i) {
// we have a method call
BytecodeUtils.Ref ref = BytecodeUtils.getRef(pool, i);
String className = ref.getClassName(pool, i);
if (className != null) {
String methodName = ref.getName(pool, i);
String methodDesc = ref.getDesc(pool, i);
fillCalls(i, className, methodName, methodDesc, calls);
}
}
if (calls.isEmpty() && annotations.isEmpty()) {
return;
}
String className = file.getName();
AnnotationsAttribute faa =
(AnnotationsAttribute) file.getAttribute(AnnotationsAttribute.visibleTag);
checkAnnotations(className, TYPE_USAGE.getMethodName(), faa, -1);
List<MethodInfo> methods = file.getMethods();
for (MethodInfo m : methods) {
try {
// ignore abstract methods
if (m.getCodeAttribute() == null) {
continue;
}
AnnotationsAttribute maa =
(AnnotationsAttribute) m.getAttribute(AnnotationsAttribute.visibleTag);
boolean annotationsChecked = false;
int firstLine = -1;
CodeIterator it = m.getCodeAttribute().iterator();
while (it.hasNext()) {
// loop through the bytecode
final int index = it.next();
final int line = m.getLineNumber(index);
if (annotationsChecked == false) {
annotationsChecked = true;
firstLine = line;
checkAnnotations(
className, m.getName(), maa, line - 2); // -2 to get the line above the method
}
int op = it.byteAt(index);
// if the bytecode is a method invocation
if (op == CodeIterator.INVOKEVIRTUAL
|| op == CodeIterator.INVOKESTATIC
|| op == CodeIterator.INVOKEINTERFACE
|| op == CodeIterator.INVOKESPECIAL) {
int val = it.s16bitAt(index + 1);
Triple triple = calls.get(val);
if (triple != null) {
Map<Tuple, Set<CodeLine>> map = report.get(triple.className);
Set<CodeLine> set = map.get(triple.tuple);
CodeLine cl = new CodeLine(className, m.getName(), line);
set.add(cl.modify()); // check for .jsp, etc
}
}
}
if (BaseMethodExclusion.isBridge(m) == false) {
SignatureAttribute.MethodSignature signature =
SignatureAttribute.toMethodSignature(m.getDescriptor());
handleMethodSignature(className, m.getName(), firstLine - 1, signature.getReturnType());
handleMethodSignature(
className, m.getName(), firstLine - 1, signature.getParameterTypes());
handleMethodSignature(
className, m.getName(), firstLine - 1, signature.getExceptionTypes());
}
ParameterAnnotationsAttribute paa =
(ParameterAnnotationsAttribute)
m.getAttribute(ParameterAnnotationsAttribute.visibleTag);
if (paa != null) {
Annotation[][] paas = paa.getAnnotations();
if (paas != null) {
for (Annotation[] params : paas) {
for (Annotation a : params) {
for (Map.Entry<String, Boolean> entry : annotations.entrySet()) {
if (entry.getKey().equals(a.getTypeName())) {
checkAnnotation(
className, m.getName(), firstLine - 1, entry.getValue(), entry.getKey(), a);
}
}
}
}
}
}
m.getCodeAttribute().computeMaxStack();
} catch (Exception e) {
e.printStackTrace();
}
}
}